sauvagine and Anxiety-Disorders

Corticotropin releasing factor (CRF) and Urocortin are important neurotransmitters in the regulation of physiological and behavioral responses to stress. Centrally administered CRF or Urocortin produces anxiety-like responses in numerous animal models of anxiety disorders. Previous studies in our lab have shown that Urocortin infused into the basolateral nucleus of the amygdala produces anxiety-like responses in the social interaction test. Subsequently, in the current study we prepared a specific CRF1 receptor antagonist (N-Cyclopropylmethyl-2,5-dimethyl-N-propyl-N'-(2,4,6-trichloro-phenyl)-pyrimidine-4,6-diamine, NBI3b1996) to examine in this paradigm. This CRF1 receptor antagonist inhibited the ex vivo binding of 125I-sauvagine to rat cerebellum with an ED50 of 6 mg/kg, i.p. NBI3b1996 produced a dose-dependent antagonism of Urocortin-induced anxiety-like behavior in Social Interaction test with an ED50 of 6 mg/kg, i.p. The compound had no effect on baseline social interaction. In addition, the CRF1 receptor antagonist prevented the stress-induced decrease in social interaction. These results provide further support for the CRF1 receptor in anxiety-like behavior and suggest this pathway is quiescent in unstressed animals.

Topics: Amphibian Proteins; Animals; Anxiety Disorders; Autoradiography; Behavior, Animal; Binding, Competitive; Brain; Corticotropin-Releasing Hormone; Dose-Response Relationship, Drug; Iodine Radioisotopes; Male; Peptide Hormones; Peptides; Pyrimidines; Rats; Rats, Sprague-Dawley; Rats, Wistar; Receptors, Corticotropin-Releasing Hormone; Restraint, Physical; Social Behavior; Stress, Psychological; Urocortins